use strict;
use warnings;
use Test::More;
use Moose::Util::TypeConstraints;
eval { Moose::Util::TypeConstraints::create_type_constraint_union() };
like( $@, qr/\QYou must pass in at least 2 type names to make a union/,
'can throw a proper error without Moose being loaded by the caller' );
done_testing;